Lubrication of machinery



y1 1935- 1 J. BIJUR I 4 2,000,913

. LUBRICATION OF momma.

Filed May 5, 1930 s shets-sheet 2.

z [5 7 ?7 f? INVENTOR 9 ram? ATTORNEY5 May 14, 1935. J. BIJUR 2,000,913

LUBRICATION OF MACHINERY Filed May 5, 1930 5 Sheets-Sheet s Patented May 14, 1935 ztooele nennwerron QEMGEIN-ERY' Joseph Bi 3111', New York,

NQYZ, assignorto Ante -i 7 Research Corporation, a, corpofatlon ofnan- Application May s ream Serial No. 4 49,76 1

18 Claims.

- pnesent; invention iszconcerned with the lubrication. of; machinem, While capableof a diversifiedirangezofutility;ifiis primarily intended: to:simplify'the'lubrication:.ofstationary machines; 7 fon'in'stance', astthose uscdfor shopor'factory equipment. .t

An objectofrtheinvention to assure correct. proportionaldistributionsofi'lubricant: to each and every-bearlngaof armachine group of: machines or complete plant to be lubricated,,and moreover. to" assureflowof.therdesiredntotalivolumfeiof lubricant tosthebeaming surfacesduring. any'periodnf: operation at the? machine on plant.

' Another'obiecfiistuprcividera lubricatlngilnstal latclon requiring: no materi'aii alter ati'oni in: the: construction" on the: lnbricatecti machiner or'plant, anttzcapabletof substantially:-universaliapplication toi .machines or? groups ofmachinesa'of' varioustypes; 0:: havingiae diverse rangei'of lubrication-re;

J quireinentse anti under: allloperatin'g conditionsoi-f' therlubricatedapparatus; to accomplish the sup ply' on lubricant continuously" automatically from at central source,;without the needtfonine spcctiom on manipulation of fittings at the: bean ings j Another object is to provide: a: simple system which: prevents a Wasteful leak of 'oilj' to the bear-- in'gs when themachine is not running; yet whitl'i"- requires no manuall opening and closing or now" valvesiwliemthemachine is started or-"sto'pp'ed.

Another ob'ectis to provide a system of the character noted above which a single control adjustment is all that is required to compensate for variation the fiow of lllbricanttoall'the 35; bearings :regardless of whethensuch variatiomlias been caused by a change in tlie condition" of? the lubricant or: in the condition of the? a paratus which handles its Among; the'chan'ges which: may. affect such r'ate' and: which maybe compensatertior'by thet'single adfiustmentt are: changesTin graule of lubricant used, changesin viscosity clue :"to temperature valnations-gen changesin the'e'fficiencmofthe pump dueto weanfon instance. i

Anothen: object isito provide means, in the nature. of. an; indicator; for. aiding. in the initial setting of the control means. to. insure vthe desired F flow rateto the respective bearings;

Another. object isto provide a-secondaiy read;

- ily readable indicating means whicli'wilfshow at a glance Whether. or not the flow ratehasi'varied from the rate'initia'llyset', or othel'ewoid's, indicate whenever resetting of thesingle'*adiustmenfi is're'quired inorclerto compensate-'fhr'variations" simply:

I preieraldlwprov-ide a pump of a c'apacitiv- (e1; I84'Z) V More specifieallythe/inVention-is especially con cer-necl lu-b ating' systems" and methotfs of a function solely; of the:pressuraon 'the-systm and. the: viscosity: of: the lubricantthereina In accotclance with a; preferred; embodiment of. the invention the central lubricantreservoiriisi to be lubricated; preferably below the lubricant outlets of the system. A1- foz' 'ce pump preferahly of: the: continuously operating gurotazy' impellert type: and. in: most instances, operated? front or synchronously with th'e machinery to:be=1ub cated: isassociated; with: the reservoir or other: Wise disposed? so that it may' pass: lubrioa'nt fnoma therreservoir intotheconduit system-under pressure; The: conduits of the system are r at: a: cross sectional area, which is large? as compared Withthe restricted pressure: 0ut1ets-. These restrictech outletsmay be drip plugs of the: general charac ter disclosed 1 inprior Patent No. 1 632 -772, dated June 14th,;L927, ca.ch drip; plugm being. rated. 0!: calibrated in accordance withthe relative needsof. itsparticulait associated. bearing, .the plugs cooperatively imposing. a flow. resistance far in ex c'essOf'the flow. resistance ofth conduits themslvesandfsuffi'cienfi to set up. a bacl'pre'ss'ureon the lubricant? V A" major problem to permit accurate ex"- p'editi bus initial predeternfifiatibn or calibration oft-lie absoluteflowrate through the-p1ugs in accordance witltth'e needs'ofthemachineantl to: I 1

ermit convenient and expeditious r'eadiiistinentwhenever-for anyfrea'son; theflbwrate-vtrriesmn teriall'y. present apparatus anal method" solve both of these problems effectively and" excess of that inquiredbythe cll-ip plii g' outlets; and provide a typass backto the reservoir for the excess oil g tl le siZe'iar-i' e correspcnding fiow resistance of the bypass, orifice being: aeljusteel to 20* suitabiy'supportednnlcr adjacentthemachir'lery insure proper subdivision of the oil stream which flows partly to the bearings and partly back to the reservoir. v

Accordingto the method which I prefer the size of the bypass (and. its corrollary, the pressure in the system) is controlled by a spring pressed valve which automatically checks drainage when the pump is not working. The resistance of this valve to flow through the bypass may be conveniently regulated manually'so that the amount of oil flowing through the bypass (i. e., the size of the bypass opening) is a function primarily of the spring pressure on the valve. j Thus by merely adjusting the pressure on the valve, the absolute flow rate through the drip plugs is variable all the way from a negligible leak or seepage to a substantial squirt of oil. In practice, for instance, it may be foundthat for a "given viscosity of oil, a pressure of 10 pounds per square inch must be maintained in the conduit system to insure adequate 'fiowto the bearings. It is merely necessary, therefore, (assuming'fiow resistance through the main length of the bypass to be negligible) to set the valve in the system at a l pound pressure whereby the valve will 7 find equilibrium in a substantially balanced condition (due to oil pressure on one side and spring pressure on the other). lubricant will be fed to the bearings and the excess will be passed directly back to the reservoir through the bypass.

. Since the absolute flow rate'of oil of a given viscosity cannot vary without an accompanying variation in pressure in the conduit system, an

3 ordinary pressure gauge in the system will afford a ready indication of flow variations.

. In the initial calibration or setting of the valve, I preferably employ a visual drip cock to which oil passes through a conventional drip plug forming part of the system.

When the system is installed on a machine, or group of machines the relative lubricant needs of each bearing are calculated in advance, but the most desirable absolute flow rate to the bearings is determined by actual tests. With the system installed and filled with lubricant the regulating valve is adjusteduntil the amount of lubricant supplied to each bearing seems to be the amount desired. Atthis time the drip cock may be observed and the number of drops of lubricant flowing from the drip cock in a minute, or other selected unit of time are noted. The pressure in the system isalso noted. For the sake of illustration, the cock may be dripping ten drops per minute and the pressure gauge may show 10 pounds of pressure.

In normal running of the machine, absolute flow rate may vary due to temperature changes, by wear on the pump, or from other causes. If it does vary the gauge will show a corresponding variation- Accurate readjustment may be effected by adjusting the pressure on the control valve until such time as the drip cock again shows the desirable 10 drops .per minute. The new reading of the gauge isagain noted and any further variations may be detected and remedied by observation of the gauge and readjustment of the valve. p

In a preferred embodiment of the invention, the reservoir, the pump, the by-pass and preferably the gauge and drip cock are associated in a unitary construction, and oil from the reservoir is passed to the pump through a filter. I

The inventionmay be more fully understood The proper amount of r through on the staggered line 3-3 of Fig.2;

Fig. 4 is a sectional plan view taken on the line i-fl of Fig. 3;

Fig. 5 is a vertical sectional view taken on the.

line 55 of Fig. 3, and

Fig, 6 is a vertical sectional view through the drip cockand associated mechanism.

In Fig. l is shown a diagrammatic view of a stationary machine installation equipped with my improved lubricating system. The machine, illustratively shown as a press, has mounted thereon at any suitable point, a lubricant reservoir R from which lubricant is pumped through a system of distributing conduits C, C and C extending along the frame structure of the machine to the various bearings B thereof. The flow of lubricant from the conduit system to the bearings is through highly restricted flow passageways, such as those afforded by the drip plugs D. One typical drip plug construction is illustrated in Fig. 1a.

Such a drip plug mayconveniently comprise the fitting H3 with a threaded end H forapplication at the bearing. High resistance to flow is determined by a pin' !2 nearly filling the longitudinal bore of the fitting. A strainer plug 53 of wool felt is provided at the inlet end of the fitting and backed by wire mesh cup Hi to intercept any solid particles entrained with the oil, which might otherwise reach the restriction crevice. Mounted in a socket at the outlet end of the body is a flap valve ma, comprising a disk having limited -movement between its seat lfib and retairier member 10c. The 'valve permits free emissionfrom the drip plug but is sucked back against its seat whenever any interpipe siphon-- ing action tends to cause suction in the line of which the valve serves as outlet. A suitable compression coupling'indicated generally at #5 serves to connect the outlet pipe to the drip plug. The diameter of the pin 12 determines the rating of the fitting, andin operation, the drip plugs proportion the distribution of lubricant to the various bearings.

As best seen in Fig. 3, lubricant from the reservoirflows througha filter chamber F to the force pump P. The lubricant expelled by the pump flows through two courses, one into the conduit system and the other through the by-pass A back to the reservoir. Flow through the bypass is regulated by a control valve V, the spring pressure on which'is adjustable by knob K to determine the pressure in the conduit system. a The reservoir includes a pair of slightly telescoped and lap welded-cup members [6, the

upper of which provides a filling neck ll normally closed by a vented cap i8. A base casting ThB 1 aooacua clamping collar 26 of less diameter than the; ill

ter chamber and defining with the walls thereof an' annular oil inlet space Elinto which oil from the well 2d flows-through the passage 28,.and fromywhich. the filter chamber F is supplied through apertures; 28 f A horizontal passageway 29 the base casting; communicates at one end with the chamber F above the filter therein and at the other end receives: a fitting 39; connected by T coupling 3! with the inlet end of conduit C from which the various drip plugs are supp ied. 7

The vertical bypass A communicates at its lower end with the passageway 2d. Between the bypass and theinlet of passageway 29, the force pump-, preferably a gear pump P is. disposed.

The intermeshing, gears 33 and 34 of the pump.

are arrangedflin suitable recesses 35 in the base casting which is closed by a cover plate 35, (Figs. 4 andg5) tocomplete the gear case.

.Preferably? the upper driving gear 38 of the pump P is formed integral with a driving shaft 31 (Fig. 5.) journaled in a sleeve 38 integral with the plate 36. Shaft 3:? has an extension 31 journaled in ansocket- 39 in the base casting. Escape of lubricant around the driving shaft 3'! isprevented by running. this shaft through a stuiling bOXl 46 at the outer end of the sleeve 38. The projecting shaft end carries a coupler ll of any suitable type adapted to be drivingly connected to any moving part of thepress or to press actuating, or actuated mechan sm; The driven gear 33 of thepump turns with or on an axle 42, the ends of which are journaled in bearing sockets plate 36, respectively.

Thevalve 'V .(Fig. 3) preferably comprises a valve disk 55, the annularly concave rim of which coacts with an upwardlyfacing convex seat 45. at the top of the. bypass passageway A.

The upper end of this passageway is enlargedat' A1 .to accommodatethe enlargedspider hub 43 i of the valve.

The vertical valve operating rod 59. has at its lower end. aball andcsocket connection 553 with the valve V. The upper end of this rod is guided in a tube 5i, the upper threaded end of which is axially adjustable through aniinternally threaded plug member 53 screwed into a collar 54 fixed tothe top of the reservoir. Tube 5! is adjustable axially byturning the knob K at its upper end and may be locked in any desired positionof adjustment by the lock nut 55 having an operating handle 56. V

The tube 55 is provided with an inwardlyspun rib portion til encircling thelreduced portion 58 below head 58 of the rod 49, thereby to prevent disconnectionioi' the rod from the tube At its lower end the tube 51 carries a head 55 flanged over a cylindrical spring housing-6t. A coiled expansion spring 61 reacting against the head 59 urges a free sliding :collar 62, which encircles the rod 29 against'a cross-pin 63 in the rod and thereby normally holds the valve in seated position.

For illustrative purposes, I' have'shown the conduit C leading downwardly (Fig. 1) and connected through a T fitting 64 with'the flow conduits. C and C which convey lubricant to the various bearingsof the machine, all-of which are disposed above the level of .thereservoir.

In the ordinary course of operation, the reservoir R. is filled with oil and the pump- P being driven from. the machinei first, fills. the conduit system withoil and then starts. to force. oil throughtain'any pressure desired inthe system. Under ordinary conditions, the most desirable absolute flow rate through the drip plugs isfirst ascere tained; the pressure necessary tomaintain such rate is determined; the valve is set to maintain suchpressure in the system and the excess lubricant furnished by the pump beyond that required: to? maintain said line pressure, by-passes back to the reservoir-around the valve V. In operation; this valve is mainta'ined' in .a position of balance with the spring pressure on one side equally balancing the fluid: pressure on the other side. The valve thus determinesthe effective cross sectional area of the bypass, or in other words, determines what proportion of the lubricant fed from the pump shall return to the reservoir. I V

For purposes of the present invention, the pump may be assumed to be continuously in operation, while the machine'is in motion and to supply a uniform volumeof oil perunit of time for any given running speed of the machine. Should the oil become more viscous due to cold, for instance, the added resistance to flow through the drip plug will result in increased back pressure in the system. 'Valve V will therefore open further and permit a larger proportion of the oil to return to Indicating means is preferably provided firstly' to expedite and facilitate the original calibration of the flow rate, secondly, to afford a ready visual indication of any variations during operation in the pressures existing in the conduit system, and thirdly to facilitate readjustment or recalibration after changed conditions.

The calibration indicator is preferably in the nature of a drip cock iii (Fig. 3) arranged under a glass dome 7i in-the top of the reservoir, and

supplied from thedistributing system by a, drip plug outlet,- of characteristics similar to those feeding the bearings. The pressure indicator is anordinary pressure gauge '52. A conduit 0 leading upwardly from the T coupling 3! connects with the" head of a second T coupling 'ld'into which the pressure gauge '72 is screwed. The indicator drip plug D is fixed in the end of passageway l8 in a, collar l6 rising from the reservoir top. This passageway is formed in an internal enlargement 1 ll of the collar. The lower end of the drip cock H3 communicates with this passageway, and the hook shaped. upper end of the cock dripsinto the reservoir and is clearly exposed through the transparent dome ii The dome may rest on a rubber packing ring 19,

(Fig. 6) laid upon an internalil'ange' 86 of the collar iii. The flangedlower end 8! ofthe dome" is clamped between ring '19" and a superimposed ring 82, the latter being forced home by a bush ing 83, screwedinto the top of the collar.

' The drip plug D which supplies the drip cook it which drips directly into the reservoir, may be of any desired rating, since it'is only of interest to note the number of drops or oil per unit of time flowing from the cook 19 when the desired flow rate to the'various bearings has been established. a

The various bearings fed from the distributing system being equipped with drip plugs of flow resistances proportioned to the respective bearing requirements, the valve V. is adjusted-until the flow to the bearings or to anyone bearing is correct. When this desired rate of supply has been established, a uniform rate of drip will be occurring from cocklil. The rate of drip from the cock may be timed in drops per minute or fraction thereof.

While the'system is in operation, any variation in the absolute flow rate to the bearings-will be accompanied by a variation of pressure in the system so that casual observation of the gauge will always determine whether or not the desired flow rate is being maintained.

, When from any cause the flow rate varies and the gauge registers a higher or lower pressure, resetting of the valve to compensate for the variation is accomplished rapidly and accurately by simply adjusting the valve V to a point where the rate of drip from the cock it comes back to normal.

When the machine is at rest the oil in the conduit system will be under no substantial pressure;

It will have little or no tendency to drain back to the reservoir, however, since the valve V will be seated, the impelling teeth of the gear pump will tend to block such flow and the filter pad itself will ofi'er a strong flow resistance. Furthermore, the-suction flap valves at the drip plugs will be drawn against their seats to stop any incipient backflow tendencies in the distributing lines.

The pressure gauge shows immediately when the reservoir is empty and requires replenishment, although an ordinary liquid level indicating column might be used, and the well 29 serve'for a reserve supply of oil if the low level on the glass were not immediately noted. i

One of the noteworthy features of the system is the fact that it functionsindependently of the quality or character of the oil which is used, since the valve adjustment will readily take care of changed conditions due to the introduction of a different grade of oil. '1

With the present installation, either a valveless drip plug, a flap valve drip plug or a valved drip plug seated by a very light spring are used rather than drip plugs embodying strong spring pressed checkvalves, since under many conditions it may be possible to operate the system at pressures which are actually lower than the pressures which would be required to open such check valves.

With the foregoing description, it will be obvious that not only novel apparatus but also novel methods, particularly controlling methods are embraced in the invention. These methods are effective to permit a single adjustment to care for varying flow conditions resulting from any cause and to facilitate both initial predetermination and quick, accurate redetermination ofthe flow rate. r

By the expression drip plug utilized in the ac.- companying claims is meant an outlet or restriction fitting havinga sufficiently high resistance to effect proper distribution between the various bearings. i

" I claim: 7 a

1. A lubricating system including in combination a central lubricant reservoir, a system of distributing conduits having invariant flow restricting outlets at the bearings to be lubricated,'rated for uniformly proportional lubricant distribution at all rates of flow, a continuously operating pump for forcing lubricant into the distributing system, and adjustable means forpredetermining the absolute rate of flow of lubricant through the outlets, and means to indicate variations in the predetermined absolute flow rate.

, 2. A lubricating system including in combination, a central lubricant reservoir, a system of distributing conduits having flow restricting outlets at the bearings to be lubricated, rated for uniformly' proportional lubricant distribution at all rates of flow, a continuously operating pump for forcing lubricant into the distributing system, adjustable means for predetermining the absolute rate of flow of lubricant through the outlets, a

pressure gauge to indicate variations in the pres-i sure in the system, and a visible volume measuring means to indicate the extent of readjustment necessary for reestablishing' the desired rate of now.

3, The combination with a lubricating system of the character which includes a central reservoir, a pump, a distributing conduit receiving lubricant fromthe pump and drip plug outlets in the conduit rated to'assure proportional flow of lubrlcant therethrough, and so highly restricted that absolute flow rate therethrough, is a function of the pressure and viscosity of the oil in the system, of means for indicating the pressure in the syster, means for adjusting such pressure to compensate for variations in the absolute new rate, and means for indicating when'the pressure controlling means has been adjusted through a range sumcient to reestablisha previously determined flow rate.

4. The combination with a lubricating system of the character which includes a central reservoir, a pump, a distributing conduit receiving lubricant from the pump and drip plug outlets in the conduit rated toassure proportional flowof lubricant-therethrough, and so highly restricted that absolute fiow rate therethrough is a function of the pressure and viscosity of the oil in the system, of means for indicating the pressure in the system, means for adjusting such pressure to compensate for variations in the absolute flow rate, and means for indicating when the pressure controlling means has been adjusted through a range suflicient to re-establish a previously determined flow rate, the. second indicating means comprising a visible flow volume indicator receiving lubricant from one of the outlets of the system.

5. A lubricating system including in combination a central reservoir, a distributing conduit therefrom having drip plugs of invariant high flow resistance at the bearings to be lubricated, the effective fiow area of the plugs being small enough to create a back pressure in the conduit, means for forcing lubricant from the reservoir into the conduit, and means to selectively predetermine the'pressure in the conduit and thereby regulate 'the absolute flow rate of lubricant through the outlets, said means including a return flow arrangement to the reservoir and a manually controlled valve to regulate the amount of lubricant passing through said return flow ar-.

a of the reservoir."

manual control lcutton and :a threaded adjustment, said manual control button being placed externally of the ireservoir and actuating the threaded adiiustment is "positioned inside '6. A lubricating system including in combination a central reservoir, a distr i'butin'g conduit therefrom having val-veless :drip' plugs at the hearings to be iubricated, the efiective flow area o'f the plugslbeing small enough to create'a back pressure in the conduit, means ier forcing lubrilcant from -the reservoir into the conduit, and ne'ans to selectively jpredetermine the pressure in the conduit and thereby regulate the absolute flow rate of lubricant through the "outlets, said means comprising aspi in-g leaded valve "in the reservoir and --ad'justalble -'ex'tericrly thereof, controlling the pressure exerted en the lubricant in the ccnduia-arrd aby-pass for excessl-ubricant irom thebonduit back to the reservoir, said bypass being controlled by said valve. V

7. A lubricating system including a reservoir, a pump-a distributing conduit into which lubricant fromthe reservoir is continuously forced by the pump, a plurality of drip plugs through which oil is distributed from the conduit, a bypass from the conduit to the reservoir, an adjustably spring loaded valve controlling flow through the bypass, means for indicating the pressure in the conduit and a flow volume indicator fed from one of the drip plugs. v

8. A lubricant supply and feed unit for central "lubricating systems including a lubricant reservoir and a pump, a flow passage from the reservoir to the intake side ofthe pump and a filter means therein, a flow passage from the discharge side of the pump and a bypass arrangement provided with fixed'and variable restrictions connecting said last mentioned passage with the reservoir, said bypass arrangement including two bypasses,

. one containing the fixed restriction and the other containing the variable restriction, said bypass "arrangement also including an indicator associated with said fixed restriction to indicate the flow therethrough;

9. A lubricant supply and feed unit for central lubricating'systems including a lubricant reservoir and a pump, a flow passage from the reservoir to the intake side of the pump and a filter means therein, a flow passage from the discharge side of the pump and a bypass arrangement con-v necting said last mentioned passage with'the reservoir, said arrangement including fixed and variable restriction means, thevariable restriction means including a spring loaded valve, and

' means for adjusting the pressure on said valve,.

said bypass arrangement including two bypasses, one containing the fixed restriction and the other containing the variable restriction, said bypass arrangement also being provided with. means to indicate the flow through'the fixed restriction.

, 10. A lubricant supply and feed unit for central lubricating systems including a lubricant reservoir and a pump, a flow passage from h reservoir to the intake side of the pump and a filter means therein, a fiow passage from the discharge side of the'pump, a bypass connecting said last, men: tioned passage with the reservoir, and fixed and adjustable flow restricting means controlling said bypass, said bypass being provided with two return flow passages respectively containing fixed and adjustable restricting means, said bypass being provided with meansto indicate the flow through said fixed restricting means.

11. A supply and feed unit for central lubricattaooogere ing, a passageway leading from the reservoir through theicasting, said passagerva'y embodying a filter means and a gear pump contrclling iiow through said passageway, the iatter communicating with the reservoir at the intake-side or the pump and :a valye-controlied bypass in the casfingtwith the reservoir "at the discharge side 01? the pump. V

12A central lubricating installation for a mechanism having 'a plurality of bearings coma ting systems includinga reservoirincluding azcasting system, said visual indicating meansbelng positioned in the other oneoi said two outlets,

13. A central lubricating installation for a mechanism having a plurality of bearings comprising a'branched distributing piping system having a single inlet and a plurality of outlets, all

except two of which lead to said bearings, high resistance flow proportioning restrictions positioned upon all of said outlet branches leading to said bearings and upon one of the branches not leading to said bearings, a spring seated check valve positioned upon the other branch outlet not connected to a bearing, means to adjust the seating pressure of said spring seated valve, means to visually indicate the rate of flow through said flow proportioning restriction not connected to a bearing so as to determine the adjustment of said spring seated valve, and a.

combined reservoir and pump unit to feed lubricant into the inlet of said piping system, said two outlet branches not feeding bearings being arranged to discharge into said reservoir 14. A central lubricating installation for a mechanism having a plurality of bearings comprising a branched distributing piping system with a single inlet and a plurality of outlets, a combined reservoir and pump unit associated with said inlet, high resistance, fiow proportioning drip plug outlets associated with all but one of said outlets, an adjustable variablepressurecontrolled restricting deviceassociated with the remaining outlet and means to visually indicate the need for adjustment of said adjustable device.

15. A central lubricating installation for a mechanismhaving a plurality of bearings comprising a brancheddistributing piping system with a single inlet and aplurality of outlets,a'com-' bined reservoir and pump unit associated with said inlet, high resistance flow proportiom'ng drip plug outlets associated with all but one of said outlets, a variable pressure-controlled restricting device associated with the remaining outlet, said remaining outlet and at least one of said drip plug outlets being arranged to discharge into said reservoir, and being provided with a visual drip discharge and the remaining outlets being arranged to feed lubricant to the bearings of said mechanism. V

16. In a central lubricating installation of the type having a branched distributing piping system, a single inlet and a plurality of outlets, a

plurality of high resistance flow proportioning drip plugs associated with said outlets and a' pump unit connected with said single inlet; the combination therewith of an absolute flow indicating device enabling rapid and accurate adjustment of the rate of feed through said system comprising an additional outlet from said distributing system, a dripplug upon said outlet and visual indicators upon said outlet before and after said drip plug respectively to indicate the pressure exerted upon said drip plug outlet, and the rate of flow past said drip plug.

17. In a central lubricating installation of the type having a branched distributing piping system, with a single inlet and a plurality of outlets, a plurality of high resistance flow proportioning drip plugs associated with said outlets and a pump unit connected with said single inlet; the combination therewith of a flow and pressure controlling arrangement comprising visual means to indicate the pressure upon and the rate of flow through said system,,an additional outlet provided with spring seated valve and means to adjust the seating pressure of said spring seated valve.

18. Ina central lubricating installation of the type having a branched distributing piping system, with a single inlet and a plurality of outlets,

a plurality of high resistance flow proportioning drip plugs associated with said outlets and a combined pump and reservoir unit connected with said single inlet; the combination therewith of a flow and pressure controlling arrangement comprising two additional outlets from said distributing system discharging into said reservoir, a drip plug upon one of said outlets and a spring seated valve upon the other of said outlets, means to adjust the seating pressure of said spring seated valve and a visual-indicator on the additional drip plug outlet respectively before and 

